The 10,573-mile journey from Heathrow is expected to take 20 hours and 20 minutes at an average speed of 520 mph. The most direct route would take the plane over Denmark, Latvia, western Russia, northeast Kazakhstan, China and the Philippines before making landfall in Australia close to Darwin.

Simulating the flights with 40 passengers and crew, most of whom will be employees, the airline said it would be subjecting those on board to a range of medical tests and assessments to check their health is unaffected by the journey length.

These pilot flights could start as soon as October 2019, while the Australian flag carrier has stated that it wants to launch the real deal in 2022.

Although the test services will be flown using Boeing jets, Qantas hasn’t yet chosen which make or model of aircraft it will use for the official launch.

Chief Executive Officer Alan Joyce has previously said the airline will choose between Boeing’s 777-8X and Airbus’s ultra-long-range A350-900ULR and -1000ULR.

Speculation over the services that will be on board the London to Sydney-bound aircraft has been rife, with possible features mentioned including a gym, children’s play area, bar and bunkbeds. Many of these ideas have since been dismissed, but Joyce says that the nearly day-long nonstop flights could feature a wellness space.

“We are, on the aircraft, looking at a zone that we’re calling the ‘fourth zone’, for people to stretch and exercise and hydrate,” he said. “And that will be part of the product that we use to launch”.